Who says large men don’t fit? Wear them right and you will look light.
For your upper clothing, it is best to stay away from horizontal stripes, unless your tall and lean. Most stripes are unflattering, specially the horizontal ones add bulk. It makes you appear heavier and shorter. Solid colors are a good choice, dark solids will make you look slimmer.
Get rid of those pants that taper at the bottom, they make you look top-heavy and overweight. Don’t wear checkered pants, this ain’t the sixties or seventies. Do not wear your belt and suspenders at the same time, trousers are not that heavy.
Lastly, wear a well polished shoes and don’t forget your socks. Keep your hair well-groomed to compliment everything and start looking good.